In order to know the potatoes nitrogen situation rapidly and accurately,promoting the efficient use of nitrogen fertiliz-er on the potatoes.Using the feature of portable hyperspectral spectrometer,digital cameras and SPAD-502 chlorophyll meter to abtain the potato digital indicators,leaf spectral and SPAD.Analysing the change status of digital indicators,leaf spectral in-dex,SPAD and production of potatoes under different nitrogen levels in two key periods.Analysing the correlation between can-opy image,leaf spectral and SPAD and production,with SPAD as auxiliary validation index,nitrogen fertilizer efficiency evalua-tion of yield to make sure potato canopy image under the most economic nitrogen application levels and leaf spectral’s critical val-ue to explore the methods of nitrogen nutrition diagnosis quickly and simply.The results show:(1 )With nitrogen levels in-creased,potato tuber formation stage and tuber bulking stage leaf spectral reflectance is the emergence of the"red shift"phe-nomenon,and the red edge parameters REP,Lwidth,FD_Max increased,Lo decreased.(2)With the nitrogen levels increased, potatoes tuber formation stage and tuber bulking stage digital indicators G/B,(G-B)/(R+G+B)decreased gradually,B/(R+G+B)increased gradually.(3)with the increase of nitrogen application rate SPAD is increased.It is obvious low nitrogen levels increase production with nitrogen increased.It is not obvious the high level of nitrogen stimulation effect.Potato canopy image, leaf spectral and red edge parameters have good correlation with SPAD value and productions,establishing the index evaluation of nitrogen nutrition abundance or lack of quantitative standard of potatoes.Indicating digital image and spectrum technology to nitrogen nutrition diagnosis of potatoes is feasible,provide research ideas and technical support for the potato accurate monito-ring of nitrogen nutrition.%为准确、快速地掌握马铃薯氮素状况,提高马铃薯对氮素的利用率,采用便携式高光谱地物波谱仪、数码相机与 SPAD-502叶绿素仪获取马铃薯冠层图像、叶片光谱、叶片 SPAD值,分析不同施氮水平下马铃薯两个关键生育时期数字化指标、叶片光谱指标、SPAD、产量的变化状况,以 SPAD为辅助验证指标,以产量为氮素施用效率评价,分析数字化指标、叶片光谱与 SPAD、产量的关系,明确最佳施氮水平下数字化指标、叶片光谱指标的临界值,以期探讨快速、简便进行马铃薯氮素营养诊断的方法。结果表明：(1)随着施氮水平的增加红边位置出现了“红移”,红边参数 REP,Lwidth,FD_Max增加,Lo 减小。(2)随着施氮水平增加数字化指标 G/B和(G-B)/(R+G+B)逐渐降低,B/(R+G+B)逐渐增加。(3)SPAD随施氮量增加而提高,施氮量增加低氮水平增产效果明显,高氮水平增产效果不明显。光谱、红边参数、数字化指标与SPAD、产量相关性较好,据此建立了各个指标评价马铃薯氮营养丰缺的量化标准。表明运用数字图像与光谱技术进行马铃薯氮素营养诊断具有可行性,为马铃薯精准氮素营养监测提供研究思路与技术支撑。
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